The War Office was a department of the British Government responsible for the administration of the British Army between the 17th century and 1964, when its functions were transferred to the Ministry of Defence. The War Office developed from the Council of War, an ad hoc grouping of the King and his senior military commanders which oversaw the Kingdom of England's frequent wars and campaigns. A number of older institutions, notably the Board of Ordnance (which dates from the 15th century), were merged to form the War Office. It worked alongside the Admiralty, and was responsible for the Royal Navy, and the (much later) Air Ministry, which oversaw the Royal Air Force.
This collection consists of original despatches, letters, and papers for the period 1732 to 1868, addressed to the Secretary at War, and after 1794, to the Secretary of State for War, and concerning Canada.